This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. In the NIH/NCRR sponsored breeding programs of the National Primate Research Centers, rhesus macaques are housed in multimale-multifemale social groups in large outdoor corrals which simulates the natural social and environmental features characteristic of the species, enhancing their reproductive performance as well as their psychological well-being. Despite the importance of this naturalistic social housing, one of the most difficult problems in socially-housed macaques is their propensity for spontaneous bouts of deleterious aggression. The long-term goal of this project is to reduce the rates of deleterious aggression in captive breeding colonies of rhesus macaques. The objective of this particular application is to enhance current behavioral management techniques by developing a set of predictive models of the within group social and group-level management factors that lead to deleterious aggression and aggression-based morbidity and mortality in group-housed rhesus macaques. Development of beneficial management practices that reduce aggression-based morbidity and mortality in rhesus breeding groups will contribute to public health by enhancing the health and welfare of rhesus macaques in breeding colonies that provide the animal resources critical for conducting biomedical research on nonhuman primates.